1. Field
The following description relates to methods and apparatuses for generating a model representing deformation of a shape and a location of an organ in a respiration cycle.
2. Description of the Related Art
A high-intensity focused ultrasound (HIFU) treatment is an operation technique to remove and treat a tumor by radiating HIFU to a tumor part (focus) to be treated and causing focal destruction or necrosis of tumor tissue.
Removing a lesion by using the HIFU is a widely used treatment techniques because it is possible to treat a human body without directly cutting into it. When the HIFU is radiated to the lesion from outside of the human body, a location of the lesion changes due to movement of the human body. For example, if a patient respires during therapy, the location of the lesion changes depending on respiration. Thus, a location (focus) to which the HIFU is radiated should also change. A method of tracking the location of the lesion that is changed by the movement of the human body and radiating the HIFU has been studied.
The location of an organ changes depending on respiration and thus a shape of the organ also changes, i.e., there is a close relation between the respiration and changes in the location and shape of the organ. In addition, since the respiration changes periodically, it is possible to estimate current locations of the organ and the lesion by using respiration signals of a patient if locations of the organ and the lesion depending on the respiration of the patient are known before therapy.
However, diagnostic images, such as, for example magnetic resonance (MR) or computed tomography (CT) images are captured at the full expiration (FE) and at the full inspiration (FI) of the patient to obtain changes in the location and shape of the organ depending on a change in the respiration of the patient. In this case, there are some cases where diagnostic images, such as, for example the desired MR or CT images are not obtained because the patient fails to temporarily stop respiration or a proper time period in which a contrast medium stays in a blood vessel cannot be calculated.